The organization carefully vetted more than 50 shelters across the country before handing out grants ranging from $3,000-$5,000 as part of an outreach program called Mutts Across America, according to a press release.

"I am amazed and humbled by the great work these shelters do, and so honored to be able to support their critical efforts on behalf of rescue animals," Lambert says.

The new surprise grants total $189,000.

Miranda Lambert Isn't Afraid to Roll Up Her Sleeves to Help Dogs

The MuttNation Board of Directors researches and selects the shelters who receive Mutts Across America grants based on a range of criteria including adoption rate, volunteerism, fiscal responsibility, community presence and more. Lambert's mother, Bev Lambert, founded the program, which has awarded more than $775,000 in total grants to more than 200 shelters so far.

"The shelter selection process proved to be more complex than initially thought. During our first year we soon discovered that all shelters are not created equally," Bev Lambert says. "We feel we have now developed a criterion list through which we hand pick the 'best of the best' shelters. Miranda and I, along with our board of directors, are honored to join forces with them in our mutual drive to benefit Mutts Across America."

In order to maintain the surprise, MuttNation does not announce the Mutts Across America recipients until the grantees have received their packages. In addition to a check and certificate, honorees also receive MuttNation Citizenship.

A complete list of Mutts Across America shelter recipients is available at MuttNationFoundation.com, along with selection criteria. The program vets shelters independently and does not accept applications.